Rotary fulcrum lever



Feb. 19, 1935. J. w. SILVER ROTARY FULCRUM LEVER Filed July 20, 1931 n pkg INVENTOR JZ-jsf M 5u. UER

94% ATTORNEY Patented Feb. 19, 1935 t Lew UNITED STATES PATENT G'FFICE 1,991,634.'l t ROTARXIFULCRUMLEVER I Jesse* Silver, Tacoma, Wash. p

I- ppucatinrulyrzo,1931,;seriaiNo. 551,917

claim.y (orto-52') Y ThisinventionV relatesV to hydraulic power devices, or`what, inthe present instance,`I prefer to term a rotary fulcrum lever hydraulic motor y andirr which there isi a cylinder containing'xed abutments with a concentrically located,`rotatable pistonY 'arranged-'tobe hydraulically actuated in opposite directions bya controlled application of-a fluid` pressure medium delivered; intov thecylinder, andiwhereirr lever arms are attached to the piston shaft for movement thereby to perform various-kinds ofwork incident` to rotation of the piston. v Y It is the principal' object of the Present invention to provide a device of the above character that is. especiallyuseful in; connection with automobile dump trucks for moving the body-to andV from its dumpingposition. l

Y It is also an ob-ject of the invention to provide a device of the above-*character that is efficient and serviceable in use; which is relatively inexpensive; which is powerful, and which' may be Vpositively controlled in its movement in either direction'.v

It is another object of. theinvention to providev novel means vrof Va Ydurable character for packing 257i the deviceagainst'leakage. 'Still ,furtherV objects ofthe invention'reside` inthe details of construction and in the combination4 of parts and intheir modeof" operation, as will hereinafter befully described." `Y `In accomplishing these and' otherobjects of the invention, I- have' provided the improved details of construction, the rpreferred' forms of which'V areV illustrated in the accompanyingl drawing,` wherem Fig; lis'aside'elevation of a portion of an automobile dump truck, illustrating LtheV application thereto of a hydraulic device embodied by the present invention. Q j

Fig. 2 is a plan View of the. hydraulic motor, shown partly in sectional detail for better illustration, and diagrammatically'illustrating the connection kof ,the'device'with a pump for moving the pressure medium. Y

Fig.. 3 is a cross sectional view, taken substan- 451 tially'on the line 3-3' in Fig 2',showing the arrangement of the pistonand abutmentswithin the Y cylinder.

Fig.` 4 is an enlarged, sectional detail, showingy one of the abutments anda portionof'the rotary piston. u l

Figf5 is a perspectiveview ofthe piston member particularly illustrating the packing stripsin the edge grooves of the pistons. Fig. 6 is a cross sectional detail, taken substantially on the line` 6 6 in Fig. 2, illustrating the intended to 'conveythe idea that this use is the manner of mounting' the lifting" and holdV back rollers on the fulcrum levers; also showing the rol-ling` connection of the rollerswith the flange of the, base beam of the truck body. 4

Figi? is a sectional detailvv taken substantially 55 Thereforegit is toA be understood that the present drawing and description` are merely fortlie purpose of illustrating and describing` the device in one of its most practical applications; and it is not only usetowhich the device may be put.

Referring rmore in detail tothe drawing- ,Y Y In Fig. 1, I have illustrated a, common type ofV automobile dump truck including 'a Vdump body l, having longitudinally extending base beams 2. xedthereto. 'The beams 2 are pivotally attached atA points near their'rearward' ends, as at'3, to the longitudinal beams 4 ofthe truck chassis, so that' f thel'body'l may be swung upwardly from its V'normal position, as shown infulllines, to the dump- 0i ing position, as'A indicated in dotted lines:

l Mounted transversely of the body, beneath it and somewhat forwardly ofthe pivots 3, .is a hydraulic motorV device embodied by the present invention and thelpllrpose of this device isto raise 33 .andlower'the truck body, 1n a, preferred com struction, the hydraulic deviceV comprises a cylin- -der 5 that is closed at its oppositelends by head` plates 6 6' securely bolted' to the cylinder ends.

The head plates are provided also with horizontal 40 flangesi'l, to which supporting, brackets S'are attached, and these brackets, as illustrated in Fig. '7,1'are bolted, or; otherwise secured, within the body frame beams 4', thereby to support the cylinder rigidly within` the truck frame, with its axiall line transversely of the body and. parallel with the line of the'pivots 3.

Rotatablycontained co-axially within the cylinder, is a pistonv member comprising a central shaft 10 that is rotatably supported at, its opposite ends within bearings fia-611; integrally formed. with the cylinder end heads.` Formedlengthwise of'the pistonshaft l0,.an df.at. diametrically'oppositesidesthereof; are pistonplates ll-l'l, which, at their ends and outer edges, fit closely to the end and side walls of the'cylinder. These edges of the Vpiston plates are longitudinally grooved, as at 12, and strips of packing material 13, are seated therein, and these strips t the wall surface to preclude leakage and are urged outwardly into close contact with the walls of the cylinder by means of a suitable number of leaf springs 14 that are placed back of the strips within the bases of the grooves. At thecorners of the pistons these strips would be suitably notched and overlapped to preclude leakage. j v

Fixed lengthwise within the cylinder to its wall at diametrically opposite sides, are abutments 15-1561.. These have keyed connections at their ends with the end plates to hold them secure, and are provided with packing'strips .16 within grooves 17 along their outer edges. These packing strips preferably would be of'i'a phenol condensation product and also would be urged outwardly by the use of leaf springs, the same as used* in connection with the packing strips of the pistons.

The opposite endsof the piston shaft 10 extend.

through and beyond ,their supporting bearings and mount a pair of fulcrum levers 18-18. These levers are keyedvto the ends of the piston shaft to rotate therewith, and they are heldin place `by means ofrcaps=21 which overlap them and which are heldby bolts 22 threadedv into the ends of the shaft. The levers are parallel and extend in the same plane of the Ycylinder axis, and are of equal length, and at their outer ends are formed with yokes 23 within which rollers 24 are mounted. These rollers are rotatablyrsupported in their yokes upon a shaft 25 whichextends between the arms and through openings in the ends thereof and are `held in place by nuts V26 threadf ed onto the ends of the shaft.

In the use of the device, as shown in Fig. l, the levers are adapted to directly overliethe frame beams 4 4 with the. rollers24 resting thereon. Also, the base beams i3---3 of the body restupon these rollers' so that rotary movement of the piston vwhich would cause the levers to swing upwardly and rearwardly, would cause the vtruck body to be swung upwardly as indicated by dotted lines in lig,V l. This movement of the piston Y is under control of a fluid or liquid pressure me.' dium such as oil which lills the cylinder, between the abutments andpistons, and which may beV pumped from one side fto` the other to move the piston accordingly. Y Y l.

Each abutment has. two 'ports formed therein leading to the outside ofthe cylinder, one portY opening intdthe' cylinder at onefface and the other opening at, the opposite face. AsY seen Vin Fig. 2, the Vabutment 1 5has ports 30 and..31 opening into the cylinder"respectively at upper and lower faces thereof. Likewise, the abutment 15e has ports 32 andY 33 opening r'espectivelyto upper and lower faces thereof. A reversable. pump is designated at V35,' and this has pipes 36 and.

37 leading` into opposite sidesthereof and pipe 36 connects through the cylinder wall with passage 33 in abutment 15a, and through ,a conduit 38, withV the passage 30 of `stator 15. Likewise,

pipe 37 connected through a port in the cylinderV walls with passage 32 of Vabutmentfla and through a conduit 39 with passage 31c of abutment l5; the connection with the pump being such'that with the pump operating in onedirec-V tion, the liquid pressure medium will` be withdrawn from one side of eachpiston and abutments andwill beforcedv intoy the cylinder at the either airfor liquid. -Y Y shaft to swing the arms inrone direction. Then, reversal of the pump reverses the flow to reverse the direction of rotation.

Movement'in one direction or the other ited by exhaustion of liquid from the suction side,

also by loosely mounted valve disks as at 40 inV Fig. 4, carried by pins 41 on the pistons 11.-1'1' back rollers 45 rotatably mounted on studs V46 `iixed in bracket piecesV 47 mounted on the cross shaft 25 closely adjacent the yokes 23 and rollers 24. These haul back rollers overlap the flangesv of the base beams 2, as seen in Fig. 6, and retain the. beams seated against the rollers both in raising and lowering the body. 'I'his connection tightened against the shaft to hold them ata position. `Should it be desired to disconnect the;V

levers from the'body, thecollars are loosened`v and adjusted inwardly lon the shaft. 'I'hen the brackets 47 may be adjusted vinwardly to Vdisengage the haul back rollers from the beaxnflange.` Y

Assembly of these parts is Vmade .easy by reason of the fact that shaft 2'5 is of. one .diameter andv Y 35 it inthe yokes and Vrollers-mounted within.then n may be slipped through openings provided 'for yokes.

Devices of this character may be made withv 'v piston and abutment or .with any desiredvnum-` ber. However, the moreused, the less willbegthe travel of the piston. Theymay be made in'differe ent sizes. and use any desirable pressuremedium.,

While, in the specication'and in the following claim, I have speciiiedthel'us'ev vof a reve'rs'abley pump 35, it is ynot intended thatv the mechanismh be limitedl specifically to., afrevers'able pumpg but that this term. shall be'. construed' VVto mean/ a pump that'isV reversible to cause a reversal indiV f l,

rection of flowof liquid or'. any',"v'alvev devices-or other equipmentin connection with a pump, that can be adjusted in a manner toV causearev'ersal'." of flower liquid. l" 'i Having thus described my'invention,` what I",I claim as new therein,.and .desire f to secure byA Letters-Patent is:-. f

K A device; of `the character described, A. com-'y .l prising a'closed cylinder, a rotary Vpistoncoaxially thereof, an abutment fixed in the cylinder having passages therein opening vinto thecylinder at.y opposite sides of the abutment and leading to the. v

exterior of the cylinderajluidpressure medium fr filling the cylinder betweenftheabutmentand v opposite sides of the piston, afreversiblepump having pipe connections lwithfthe ,outer 'ends of.. said passages of the abutment andoperable toy cause a forcible delivery ofthe pressure mediumf from one side to the other of-,the piston -to actuate'I i it accordingly', andjvalve.platesmounted byY the ff,

of the suction passageat theend of movement piston in position' to close over the innerend,

of thepiston in either direction. e i-r,

other sides of the pistons to rotate r the pistonVV Y of nquidff provides not only for positive raising .of the v under power delivereg .A 

